Tehran University Medical Journal

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Background: During general anesthesia in patients with mediastinal mass compression effect on the heart, great intra thoracic vessels, or tracheal tree can lead to decrease venous return, cardiovascular collapse or tracheal obstruction. These complications may be worsened after induction of general anesthesia or prescribing muscle relaxants.
Case report: A twenty one years old female with huge anterior mediastinal mass was a candidate for right sided thoracotomy. Compression effect on the adjacent structures has been reported in chest CT scan and in echocardiography. Awake oro-tracheal intubation was performed in sitting position. Then patient positioned to left lateral decubitus for thoracotomy During surgery asystole occured. We changed the position to remove compression effect on the heart and great vessels. Fortunately these maneuvers changed asystole to sinus rhythm.
Conclusion: Decreased thoracic muscular tone and removed spontaneous ventilation after muscle relaxant may threaten patient’s life. Change of patient’s position can remove the compression effect.

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Background: We report a case with apparent resistance to local anesthetics. While regional anesthetics failure are often attributed to technical failure, the clinical presentation and medical history of this patient suggests a true resistance to local anesthetics.
Case report: A 28 years old man was scheduled for elective orthopedic surgery for right sided tibial bone fracture, and decision of spinal anesthesia was made. There was a questionable history of multiple prior episodes of local anesthetic unresponsiveness (Interscalan block, local infiltration for lipoma resection and dental surgery). Spinal anesthesia was performed and sensory or motor blockade was not obtained despite any evidence of technical problems. The surgical procedure performed under general anesthesia and skin analgesia (local infiltration of lidocaine 2% and bupivacaine 0.5% to forearm), did not achieve, the day after surgery.
Conclusion: While the failure rate of spinal anesthesia has been shown range from 4 to 13% and is often attributed to technical failure, this particular case showed a true resistance to local anesthetics.

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Background: Acupuncture is one of the most effective methods of alleviating pain in different situations including chronic and acute pain management. The aim of this study was to evaluate the effectiveness of acupuncture in the reduction of post-operative pain after hernia repair.

Methods: In this placebo-controlled, double-blinded clinical trial, we enrolled 60 male patients aged 30 to 60 years old with an ASA physical status of I or II undergoing elective inguinal hernia repair under general anesthesia in Imam Khomeini Hospital, Tehran, Iran. All patients experienced standard anesthetic and surgical procedures. After completion of the operation and while the patients were still under general anesthesia, they were randomly assigned to two groups: acupuncture (with stimulation of GV2, GV4 and SP6 points with sterile acupuncture needles), and control (with sham acupuncture stimulation). After termination of anesthesia, during the first six hours, the pain intensity was evaluated hourly. Pethidine (25 mg) was administered for the patients when necessary. Pain intensity and pethidine use were recorded and compared between the two groups.

Results: The mean age of two groups did not differ. Pain intensity was significantly lower in the acupuncture group between the second and fifth postoperative hours. Moreover, pethidine use was significantly lower in the acupuncture group versus the control group during the first six hours after surgery (12.07±7.5 mg vs. 12.91±6.5 mg, respectively p=0.0001).

Conclusion: The application of acupuncture in patients is associated with a marked decrease in pain after inguinal hernia repair and does not have any serious complications. Acupuncture is strongly recommended for all post-operative patients.

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Background: Cardiac herniation is a fatal post pneumonectomy complication. We report the signs, clinical findings, diagnosis and management of a patient with post pneumonectomy cardiac herniation.

Case report: A 34-year-old man with lung cancer underwent left pneumonectomy with partial pericardiectomy in the right lateral decubitus position. At the end of the surgery, cardiovascular collapse, severe bradycardia, desaturation and elevated airway pressure occurred just after repositioning the patient to the supine position. This patient survived as we returned him to the right lateral decubitus position and avoided the use of positive pressure ventilation.

Conclusions: Attention to the acute complications of pneumonectomy, diagnosis and rapid therapeutic interventions is essential in post pneumonectomy care.

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Background: The risk of atherosclerosis and cancer is high in hemodialysis (HD) patients. There is evidence that HD causes oxidative stress. However, the causative factors of oxidative stress are unknown. It has been suggested that HD imposes an additional oxidative stress on patients with chronic renal failure by activation of granulocytes on dialyzer membranes resulting in an imbalance between oxidants and antioxidants. In this regard, a number of reports, either measuring specific analytes or enzymes, or estimating the total antioxidant activity of the plasma have given contradictory and inconclusive results. To investigate the oxidative stress status in Iranian HD patients, in this study, we evaluated GSH and FRAP levels along with Ca and pH in the blood of these patients.

Methods: Along with 20 healthy age and gender matched control subjects, 24 patients underwent dialysis, three times per week, for four hours in each session. Before and after dialysis, blood was taken for biochemical and liver function tests and to evaluate oxidative stress markers and measure Ca and pH levels.

Results: There was a significant decrease in FRAP and GSH levels after dialysis compared to those before treatment. Dialysis caused an increase in pH and Ca levels compared to levels in control subjects after dialysis.

Conclusion: In general, before dialysis, there is a balance between oxidants and antioxidants however, due to higher levels of oxidants as well as the possible binding of antioxidants to the dialyzer membrane during dialysis, an imbalance occurs. The instability in the balance of oxidants and antioxidants may be the major cause of cellular oxidative damage found in HD patients. This study indicates that there is a significant level of oxidative stress in renal chronic patients and this stress is augmented by dialysis. Antioxidant therapy should be considered in these patients.

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Background: The insertion of endotracheal tube is essential for most surgical operations, mechanically ventilated patient in ICU wards, During cardiopulmonary resuscitation and so for transport of patients. The aim of this study was determination of airway related distances in Iranian patients.

Methods: In a cross- sectional study during year 2007 in Imam Khomeini university Hospital a total of 75 ASA class I and II patients who were admitted to pulmonary ward evaluated for determination of incisor-vocal cord and incisor- carina distances. The nasal nare- vocal cord distance was determined too.

Results: A total of 71 patients, 45(63%) male and 26(36.6%) female were evaluated. The Incisor-vocal cord distance in males and females was 16.83±0.75mm against 15.04±1.12mm (P=0.03). The difference of nare-vocal cords and Incisor- vocal cord  distances was 2-3Cm

Conclusions: There was direct association between height and tracheal length in the study patients. The tracheal length (suitable insertion depth) in our patients was different from the recommendations (23 & 21 Cm for men and women) for non- Iranian, 25.9 versus 22.6 for Iranian men and women respectively. The difference of nasal nare-vocal cord and upper incisor-vocal cord distances in our patients was 2-3 cm, the lower range of accepted or reported one. We offer to do another experience with larger study group to apply the data to Iranian population.

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Background: Acute hepatitis is upon serious complications of halothane usage, can be associated with 50% mortality in severe cases. Use of halothane as inhalational anesthetic or use of it for maintenance of anesthesia is restricted/ prohibited in USA and most European countries. The occurrence of icterus and elevated liver enzymes after halothane anesthesia may be due to the drug induced hepatitis.

Case report: we report a 28 year old woman with acute hepatitis after cesarean section under halothane anesthesia, fortunately discharged to home 40 days after that. Other causes of hepatitis became role out in the patient.

Results: The usage of halothane should be restricted/ prohibited in our country because of its potentially serious and fatal complications and so existence of more safe but expensive alternatives.

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Normal 0 false false false EN-GB X-NONE AR-SA MicrosoftInternetExplorer4 Background: The prediction of the probability of difficult intubation and the associated problems before Induction of anesthesia could be lifesaving. The aim of this study was the investigation of association between the stage of thyroid cartilage prominency and laryngoscopic view for predicting the difficult intubation.
Methods: Five hundred and thirty five patients aged 18-60 years old, with prominent thyroid cartilage, "Adam's apple", enrolled in a cross -sectional study based on the stage of "Adam's apple" and the relationship with laryngoscopic view. After induction of anesthesia, laryngoscopy performed and laryngoscopic view of larynx was recorded, and analyzed according to Modified Cormackand Lehane's Scoring.
Results: No significant association between laryngoscopic view and thyroid cartilage prominency staging was observed. There was no significant relationship in females and aged under 50 y.o. The relationship in males with poor correlation coefficient was significant. The results are as follows: [male :(p=0.028, r=-0.096), Female: (p=0.821, r=0.082), <50 yrs: (p=0.87, r=0.007) no significant association for age decades and thyroid cartilage prominency stages, were observed. In ages above 50 y.o, difference was significant. Thirty patients had a laryngoscopic view in which the tracheal rings were visible just bellow the vocal cords.
Conclusions: As the increased age was related to laryngoscopic view and thyroid cartilage prominency stage it seems that there is relationship between ages over 50 y.o and difficulty of laryngoscopic view or intubation. With the observation of a view different from the grade I Cormack and Lehane's scoring, we named it the "stage Ia" that the tracheal rings are visible bellow the vocal cords during laryngoscopy.

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Normal 0 false false false EN-GB X-NONE AR-SA MicrosoftInternetExplorer4 Background: Bispectral index (BIS index) shows the depth of anesthesia. The effects of drugs on BIS and amnesia are different. This study was performed to evaluate the association between two different sedative regimens on BIS and amnesia.
Methods: In this clinical trial, 60 patients who needed elective orthopedic surgery under regional anesthesia with intravenous sedation were elected. Patients divided in two equal groups based on sedation protocol by block randomization method: midazolam plus fentanyl group (MF group) or propofol group (P group). Dose of sedative drugs were adjusted according to clinical findings of sedation. Depth of sedation in all patients, preserved in four based on modified Ramsey Sedation Score. Patients questioned about spontaneous recall after full awakening in recovery room. Recall of any event during operation considered as failed amnesia. Correlation of BIS index with recall was measured in two different groups separately.
Results: The frequency of recall was 2 (6.7%) in P group and 10 (33.3%) in MF group (p=0.01). The mean± SD of BIS in P group was 76±5 (68-91) and in MF group was 93.4±5 (77-98) (p<0.001). The difference of BIS in patients without amnesia (p=0.019) and with amnesia (p<0.001) in two groups were significant, respectively. No delay in recovery was observed.
Conclusion: Although the Modified Ramsey Sedation Score and clinical sedation indices were the same, but BIS in patients varied in a wide range. Hypnotic drug was a main determinant of BIS score and amnesia.

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Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 Background: The insertion depth of tracheal tube differs based on sex, age, position of head and neck, type of surgery, and anatomical consideration. The aim of this study was to determine the airway related distances in Iranian patients with a non-invasive, and accurate method, the computerized reconstruction of High Resolution CT (HRCT) Virtual Bronchoscopy.
Methods: A total of 140 Iranian patients who became candidate for sinus and chest tomography, were enrolled in a cross- sectional study in Imam Khomeini Hospital Complex, Tehran, Iran, from 2006 to 2008. After reconstruction of airway related distances, Incisor- Vocal cord (IVD), Vocal cord- Carina (VCD) and Incisor- Carinal (ICD) Distances were determined.
Results: A total of 140 patients were evaluated, while 70(50%) were male. There was no statistically significant difference between age groups, sex and BMI in study patients. The measured IVD were 145.5±9.7 (males), 127.29±6.3 (females) and 136.43±12.29mm (total). For VCD, the distances were 131±13.99 (males), 122.59±11.7 (females), and 127.09±13.65mm (total). The measures for ICD in males, females, and total of patients were 277.17±16.63, 249.88±11.54, and 263.52±19.66mm respectively.
Conclusion: The insertion depth for fixation of endotracheal tube in Iranian adult patients is the same as that of anesthesia textbooks. There were no statistically significant difference between our study data and previously measured distances using invasive and less accurate methods. Virtual bronchoscopy is a noninvasive and accurate method based on reconstruction of computed tomographic images and the reconstructed images of tomography could be useful in measuring and assessment of airway anatomy.

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Background: Acute Necrotizing Mediastinitis (ANM) is a lethal disease that without antibiotic therapy and surgical Intervention has a mortality rate about 40% in best medical centers. With development of imaging technology (spiral CT- Scan) and shortening in time of diagnosis and surgery, the outcome and prognosis of the patients are improved. The surgical modalities are trans- cervical and trans- thoracic approaches.
Case series: We present a series of four patients with acute necrotizing mediastinitis that admitted to thoracic surgery ward in vali-e-asr Hospital in Tehran, Iran, during years 2009 and 2010. A 31years old woman and three male patients with ages 21, 25 and 63 years. Odontogenic infection was the cause in two cases while pharyngeal perforation and cervical esophageal perforation were the causes of acute necrotizing mediastinitis the others.
Results: Mean±SD of hospitalization time was 24±6 days. Infection of cervical space (periviceral spaces) and the superior mediastinum were found in all patients while extension of infection below the carina was found in two of them. All patients were operated by trans- cervical approach. One patient was operated by trans- thoracic approach. All patients were discharged with good general condition.
Conclusion: Early usage of spiral CT- scan for diagnosis of acute necrotizing mediastinitis and early drainage with trans- cervical approach could be life saving in acute necrotizing mediastinitis patients with good results.

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Background: Lung separation is the basis of thoracic anesthesia, which is performed by different instruments. Checking probable malpositioning of tracheal tube needs fiberoptic bronchoscopy. The aim of this study was to compare respirator suggested compliance with fiberoptic findings in detecting major tracheal tube malpositioning.
Methods: A total of 256 patients undergoing thoracic surgery with double-lumen tracheal tube insertion in Imam Khomeini Hospital, Tehran, Iran, during 2010-11 were divided into three groups (n=86). We used left-sided double-lumen tube (DLT) for left or right-sided surgeries (groups 1 and 2), and right-sided DLT for left-sided surgeries (group 3). The position of the tubes was evaluated and compared using bag compliance versus fiberoptic bronchoscopy.
Results: The mean age of the study population was 44.7±13.4 (16-73) years, while 155 (59.9%) were male. The sensitivity, specificity, positive and negative predictive values, and the accuracy of bag compliance test for left-sided DLT in supine position were 40% (95% CI: 20-60%), 99% (95% CI: 96-99%), 84% (95% CI: 54-94%) 92% (95% CI: 88-95%) and 92% (95% CI: 87-95%), respectively. The above-mentioned variables for lateral decubitus position respectively were 27%, 98%, 76%, 89%, and 88%. Malpositioning was more prevalent in right-sided DLTs (P=0.02).
Conclusion: Based on the results of this study, and the high specificity, positive predictive value, and accuracy of bag compliance test, its use is encouraged as an alternative to fiberoptic bronchoscopy for checking DLT position, specially, in emergent surgeries or when fiberoptic bronchoscopy is unreachable due to lack of expertise or personnel.